The amended document also notes that how Wood got into the water was never "clearly established."

Wood, a three-time Oscar nominee, drowned in the waters off Catalina Island in November 1981. Sheriff's investigators renewed their investigation last year shortly before the 30th anniversary of her death.

The sheriff's department says the case remains open and that the coroner's office made the ultimate decision to amend the death certificate. Detectives have instructed coroner's officials to not discuss the case.

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